16f84=16f84a?

[xjackal]

are they the same.or am i wrong that i am trying to write to a 16f84a chip?

 

[kinjalgp]

I guess there is some difference between them because the PICSTART PLUS Device list in MPLAB IDE seperately lists both these devices.

 

[TheAnimus]

microchip claim the 16F84A to be a drop in replacement, if u read the datasheet for teh 84A there is actually a list of differnces, it can run twice as fast, and there are some almost bug fixes.

Most code can just be whacked onto an 84A with no difficulty at all.

<RANT>
on a side note, anyone care to tell me y people like the 84A so much?! i just don't see y, for most projects it has either too many or too few pins, no internal osc etc.

i think the 12F629 should be used more 5 gpio pins, + 1 only input.
most things i find thats all i need, its cheap int osc. dac version available.
</RANT>

 

[xjackal]

my problem is that i cant program my pic when i built those schematics for 16f84 but then i realised i got 16f84a because i didnt know the difference then i was newbie.so is the problem that i cannot program my chip is because i didn t make it for 16f84a or doesnt it matter so much!

 

[kinjalgp]

doesnt it matter so much!

It does matter if the programming technique has been revised in new version.

 

[TheAnimus]

Ok after a quick glancing over the datasheet, i can't see any physical differnces however MicroChip warn that there might be software issues when programming, see:
https://www.microchip.com/download/lit/migrat/30072b.pdf

if your building your programmer on the cheap, try building one for a 16f870 family, these can be low-voltage programmed. Meaning hook upto parport with a couple of resistors and your away!

 

[tommyc2000]

999

the serial programming thru rb6 and rb7 doesnt matter at all, programming for 16c84 or 16f84 or 16f84a is the same for all....tried it many times, always works

i still dont understand why they added this low voltage programming thing for....

the serial programming is just too perfect for me

 

[seanw]

Try using a fast PC for programming the PIC16F84A. I could not Flash it with my 333MHZ laptop, but works everytime w/ 2.0 & 1.7 GHZ PC's.

 

[Exo]

Then there's something wrong with your 333 or you're using crappy programming software.
I programmed many pic's using my old 486 sx

 

[MarkK]

Try using a fast PC for programming the PIC16F84A. I could not Flash it with my 333MHZ laptop, but works everytime w/ 2.0 & 1.7 GHZ PC's.

If you are using a programmer that doesn't have its own 13V supply then the voltage provided by your laptop RS232 probably isn't high enough.
Mark K.